let hello = "Hello, World!"
print(hello)  // 输出：Hello, World!

// 创建空字符串
let emptyString = ""
print(emptyString.isEmpty)  // 输出：true
let anotherEmptyString = String()
print(anotherEmptyString.isEmpty)  // 输出：true

// 从字符数组初始化
let characters: [Character] = ["H", "e", "l", "l", "o"]
let stringFromCharacters = String(characters)
print(stringFromCharacters)  // 输出：Hello
